The thermal, flow, and heating properties of unrefined fish oils (anchovy–sardine oil derived from fish
processing waste, and unrefined salmon oil derived from salmon discards) blended with bunker ‘A’ oil
(a common heating oil) were investigated. The rheological properties of the blends were examined and
modeled using an Arrhenius equation approach. The onset of thermal degradation of waste fish oil, salmon
oil and bunker ‘A’ oil were 187 C, 229 C and 75 C respectively and complete decomposition of the
oils occurred between 500 and 550 C. The flow behavior index of the oil/blend samples was less than
one, which indicated that the fish oil/blend exhibited non-Newtonian fluid behavior. More so, all samples
showed decreasing viscosity with increasing shear rate indicated that the samples and their blends
exhibited a shear-thinning non-Newtonian behavior. The average heating value of anchovy–sardine oil,
unrefined salmon oil and bunker fuel oil were 38.69, 39.51 and 43.36 MJ kg1 respectively. The energy
barrier to flow and viscosity of the blends decreased with increasing quantity of fish oils in
fish-bunker mixture.